<template>
  <div class=nav-bar :class="{'is_fixed':isFixed}">
      <div class="container">
          <div class="pro-title">
              {{title}}
          </div>
          <div class="pro-param">
              <a href="javascript:;">概述</a><span>|</span>
              <a href="javascript:;">参数</a><span>|</span>
              <a href="javascript:;">用户评价</a>
              <slot name="buy"></slot>
          </div>
      </div>
  </div>
</template>

<script>
export default {
    name:'nav-bar',
    props:{
        title:String
    },
    data(){
        return{
            isFixed:false
        }
    },
    methods:{
        initHeight(){
            let scrollTop=window.pageYOffset||document.body.scrollTop||document.documentElement.scrollTop;
            this.isFixed=scrollTop>152?true:false;
        }
    },
    mounted(){
        window.addEventListener('scroll',this.initHeight)
    },
    destroyed(){
        window.removeEventListener('scroll',this.initHeight,false)
    }
}
</script>

<style lang="scss" scoped>
@import '@/assets/scss/config.scss';
@import '@/assets/scss/mixin.scss';
  .nav-bar{
    height:70px;
    line-height:70px;
    border-top:1px solid $colorH;
    background:$colorG;
    z-index:10;
    &.is_fixed{
        position: fixed;
        top:0;
        width:100%;
        box-shadow:0 5px 50px $colorE;
    }
    .container{
      @include flex();
      .pro-title{
        font-size: $fontH;
        color:$colorB;
        font-weight:bold;
      }
      .pro-param{
        font-size: $fontJ;
        span{
          margin: 0 10px;
        }
        a{
          color:$colorC;
        }
      }
    }
  }
</style>